Key Diseases

Understanding key cereal diseases is a fundamental part of disease control. Diseases can be taking hold long before symptoms are visible so planning a preventative strategy and taking into account key spray timings should be at the core of any fungicide programme to ensure you maximise yield potential.

Wheat Diseases

There are several diseases that can affect your wheat crop but we have identified 4 key ones that could impact yield:

  • Septoria
  • Yellow rust
  • Brown rust
  • Mildew

Yellow rust

* Yield loss potential is up to 50%
* Cycles every 7-14 days, dependent on temperature
* Favours humid conditions
* Early control at T0 is critical to maintain yield and quality.


* Number one foliar disease in wheat
* Can reduce yield by up to 50%
* Latent period of 14-28 days (around 350 day degrees)
* Don't rely on curativity, target with your T2 spray to prevent yield and quality loss.

Brown rust

* Lifecycle 7-14 days, dependant on temperature
* Favoured by mild winters and warm springs
* Needs green bridge for survival
* Higher temperature range favours late season infection


* Lifecycle can be 5-14 days under optimum conditions
* Favoured by fertile crops, high seed rates and mild winters
* Needs high relative humidity for infection and survival
* Generally low yield loss, although early infections on backward crops can be an issue